Improvement in metallic cartridges



l.` M. MILBANK.

IVI/711411( 1 UNITED STATES PATENT OFFICE.

ISAAC M. MILBANK, OF GREENFIELD HILL, CONNECTICUT.

IMPROVEMENT IN METALLIC CARTRIDGES.

Specilication forming part of Letters Patent No. 125,830, dated April 16, 1872; antedated April 5, 187

To all whom 'it may concern Be it known that I, ISAAC M. MILBANK, of Greenfield Hill, in the county of Fairfield and State of Connecticut, have invented and made an Improvement in Cartridges for Fire-Arms; and the following is declared to be a correct description of the same.

Cartridges have been made with a projection containing the fulminate at or near thc middle ofthe base, but the said projection has been struck upon the side `with a hammer, or else an anvil has been crimped into the metal to prevent the blow driving the fulminate int-o the powder-space and to furnish a resistance to eti'ect the detonation. Both these forms are objectionable, because the projecting teat is not adapted to lire-arms that have hammers acting in lille with the axis of the gun; and in the case where au anvil is introduced it has to be inserted at the time the plastic fulminate is inserted, and there is risk ofthe anvil not being thoroughly secured in place; besides, the parts are expensive to make, and the cartridge cannot be recharged with fulminate. a

My invention is made for obvating all the aforesaid difficulties; and consists in a cartridge havinga dovetailedor conical t'ulmiuatechamber made in the sheet metal of the case, with the smaller endof the cone forming the mouth of the fulminate-chamber, and into this chamber the fulmiuate or detonating material is introduced in aplastic state, mixed with sand or pulverized glass, that sufficiently fills the space to form a resistance and cause the explosion of the fulminate by a blow upon the center of the rear of the base.

By this construction the conical mouth of the fulminate-chanber directs the whole force of the detonatiou into the powder and insures the explosion of the same, instead of the iiash being deflected from the powder, as is usually the case where an anvil is made use ot', and frequently causes the cartridge to miss tire.

In the drawing, Figure l is a section of the sheet-metal case b before the fulminate-chamber c is spread into a conical form. Fig. 2 is a section ofthe base a. Fig. Breprescnts the case after the base al has been put upon the chamber o and the latter pressed endwise to flatten the same and spread the. chamber into the conical form necessary for receiving the detonat-ing material, and simultaneously secur ing the base a to the case. Fig. 4 shows a slightly different form of base, s0 y as to make the conical fulminatc-chamber deeper. Fig. 5 shows the same conical fuhninate chamber, but without the external base. In this case the sheet metal is folded around the fulminatechamber, and I remark that the base of the case may be. strengthened by solder; and, it' desired, a ring may be soldered around the case to take the place of the hollow flange e.

The detonating material may be varnished after it is pressed into its conical cavity, or ad` hesive material may be added to the mixture ot' fulminate, and ground glass or similar grains of hard material.

The base a may be more fully secured to the case by solder, and, if desired, the rear end of the fulminate-chamber may be made concave, asin my patent for primers dated May 3l, 1870.

I do not claim a conical chamber in a cartridge-case for thereceptiou of a metallic anvil against which the fulminate is exploded.

I claim as my invention- A primed cartridge-case, in which the fulminate described is introduced into a conical chamber, substantially as described, whereby the ordinary anvil is dispensed with.

Signed by me this 14th day of July, A.. D. 187 1.

I. M. MILBANK.

\\'itnesses:

HAROLD SERRELL, GEO. T. PINCKNEY. 

